Send to

Choose Destination
See comment in PubMed Commons below
Talanta. 1997 Dec 19;45(2):451-62.

Redox method for the determination of stability constants of some trivalent metal complexes.

Author information

  • 1Instituto de Tecnologia Quimica e Biológica, Rua da Quinta Grande, 6, Apartado 127, 2780 Oeiras, Portugal; Instituto Superior Técnico, 1096 Lisboa codex, Portugal.


Stability constants determination of very stable metal complexes using the redox method, based on the equilibrium of Fe (3+)Fe (2+) followed by a couple of platinum/reference electrodes, was undertaken and tested to complexes of some trivalent metal ions with well known polyaminopolycarboxymethylated linear ligands (edta, nta, cdta, dtpa and ttha) and also to some new macrocyclic ligands. SUPERQUAD program was used for the calculations, after adaptation of the experimental data. The method proved to be very useful for Fe(3+) and In(3+) complexes, if no polynuclear complexes are formed or/and if the kinetics of the complexation reaction is not very slow. However, for the Ga(3+) complexes the applicability of this method is very limited and the competition with OH(-) using the displacement reaction which occurs at pH higher than 6 with formation of Ga(OH)(4)(-) seems to give more accurate results. A complete data of stability constants for the case of the complexes of ttha with In(3+) is given.

PubMed Commons home

PubMed Commons

How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Elsevier Science
    Loading ...
    Support Center